Ice fishing is a popular sport in areas where fresh water lakes freeze over in the winter. Ice is safe to walk on when it reaches 4 or 5 inches in thickness, and in colder climates the ice may reach a depth of 3 feet or more. The fishing is conducted through a hole drilled in the ice ranging from 5 inches to 13 inches in diameter which is cut by either a manually operated or a motorized ice auger. Ice augers powered by a power unit having a gasoline engine are currently popular and are available from many manufacturers.
When a fish is hooked under the ice, it must be pulled up through the hole and, while that is not a problem with smaller fish, many large fish are lost when they must be turned to come up into the hole through which the fishing line extends. The vertical sidewall surface of the hole forms a 90.degree. angle with the bottom of the ice so on most occasions the fish on the hook must make a 90.degree. turn to enter the bottom of the hole. Many large fish are lost at this point because of the extra stress placed on the fishing line and hook when extra pressure is applied to the line to pull the fish around the corner and, in some cases, a sharp edge formed at the bottom of the hole may even cut the line.